Carlisle, and the submarines USS Pilotfish and USS Apogon. In addition to his work in the water, a key aspect of Delgado's early work was documenting the remains and environmental conditions surrounding shipwrecks exposed as a result of beach erosion. He was one of the first archaeologists in the United States to conduct such studies, beginning with the wrecks of the schooner Neptune, and the Golden Gate National Recreation Area, the steamer Pomo at Point Reyes National Seashore, and in 1985, he led a detailed survey of beached shipwreck remains at Cape Hatteras and Cape Lookout National Seashores in North Carolina. His Master's Thesis was based on his work with the beached wreck of the Gold Rush steamer Tennessee, which lies within the boundaries of the Golden Gate National Recreation Area in Tennessee Cove. After a one-year sabbatical from the NPS in 1984-1985 to attend East Carolina University, Delgado gained a master's degree in Maritime History and Underwater Research and was subsequently assigned by NPS Chief Historian Edwin C. Bearss to work as project historian on the USS Monitor project with the National Oceanic and Atmospheric Administration(NOAA). That work led to a series of historical and archaeological context studies, and Delgado personally completed the successful nomination for Monitor's designation as one of the first National Historic Landmark shipwrecks in the United States. He subsequently completed the National Historic Landmark studies for the wrecks of USS Arizona and USS Utah at Pearl Harbor. As of 2018, there are only nine National Historic Landmark shipwrecks or hulks that have been designated by the Secretary of the Interior. Maritime preservation In 1987, Delgado became the first Maritime Historian of the National Park Service and as such, the founding chief of the NPS maritime preservation program, the National Maritime Initiative (NMI). The NMI at that time functioned as the maritime preservation program for the entire federal government. The Initiative is now known as the NPS Maritime Heritage Program In this role, Delgado oversaw the creation of classification standards and guidelines for preservation and documentation. Delgado was the principal author of the National Register of Historic Places’ guidelines for nominating historic ships and shipwrecks and co-authored the National Register Bulletin for nominating historic aids to navigation. As a guiding principle of the National Maritime Initiative, Delgado, based on his experience at Golden Gate National Recreation Area, insisted on a physical inspection of the nation's large